Thanks. Tried advanced search with no luck. The device is Siemens and
they used to have a download for windows 2002 upgrade. This is no
longer available. Does anybody knows/have the upgrade file?

No, it's generally the responsibility of who's brand name is on the
device (who, of cours , generally gets the updates from the OEM.)  This
is particularly true of PPC Phones, because additional customizations are
added by the carrier (data settings, logos, etc.)  For example, although
the current T-Mo MDA and Cingular 8125 are both re-branded HTC Wizards,
you get the MDA updates from T-Mo, and the 8125 updates from Cingular.

Since the OP's PPC phone WAS T-Mobile branded, T-Mobile IS (was?) the
"official" distributor of any upgrades.

Unfortunately, that window of opportunity has closed- like many PPC
upgrades, it was only offered on T-Mo's website for a limited time- about
a year or so, IIRC.  Whether that's due to some Microsoft licensing
restriction or just the "manufacturer's" lack of interest, I don't know.

The T-Mo PPCPE (Pocket PC Phone Edition) was the original HTC PPC phone
(also sold as the Siemens SX66, and the O2 XDA,) and was the inspiration
for the xda-developers.com website that deals with tweaking, upgrading
and hacking HTC PPC phones.  It's very likely the upgrade is still
available there in one form or the other.  I suspect the legality of
finding it there is questionable, but my sense of legality and ethics
gets fuzzy when it comes to years-old abandonedware...

The ROM image running on my T-Mo MDA comes from that site.  Someone
calling himself Xelencilin took the original HTC ROM and added just the
necessary T-Mo customizations (data settings, etc.) to create a custom
image free of a lot of T-Mo "deadweight," and most importantly (for me)
restored the orginal HTC dialer skin that T-Mo chose to replace with a
garish pink and white one (to match the color scheme of their logo!)